From now to 2030, deforestation in the Amazon could release 55.5 to 96.9 billion tons of CO2. At the upper end this is more than two years of global greenhouse gas emission. In addition, the destruction of the Amazon would also do away with one of the key stabilizers of the global climate system.

“The importance of the Amazon forest for the globe’s climate cannot be underplayed,” says Dan Nepstad, Senior Scientist at the Woods Hole Research Center and author of the report.

“It’s not only essential for cooling the world’s temperature but also such a large source of freshwater that it may be enough to influence some of the great ocean currents, and on top of that it’s a massive store of carbon.”

Current trends in agriculture and livestock expansion, fire, drought and logging could clear or severely damage 55% of the Amazon rainforest by 2030. If, as anticipated by scientists, rainfall declines 10% in the future, then an additional 4% of the forests will be damaged by drought.

Global warming is in fact likely to reduce rainfall in the Amazon by more than 20%, especially in the eastern Amazon, and local temperatures will increase by more than 2°C, and perhaps by as much as 8°C, during the second half of the century.

With further destruction of the Amazon forests, less rainfall in India and Central America is anticipated, as would rainfall during the growing season in the grain belts of the US and Brazil.

Strategies to halt deforestation in the Amazon include minimizing the negative impacts from cattle ranching and infrastructure projects to rapidly expanding the existing network of protected areas.

“We can still stop the destruction of the Amazon, but we need the support of the rich countries,” says Karen Suassuna, a climate change analyst at WWF-Brazil. “Our success in protecting the Amazon depends on how fast rich countries reduce their climate damaging emissions to slow down global warming.”

Climate change is initiating and speeding up the vicious circle. Today, carbon from forest conversion to cattle pastures and agriculture in the Brazilian Amazon is seeping into the atmosphere at a rate of 0.2 to 0.3 billion tons per year. This number can double when severe drought increases forest fires. Emissions from all Amazon countries are double the figures for Brazil.